Electronic thermostats often have a keyboard lock feature. By locking the keyboard, keys are consequently not operational. There are several reasons to lock a keyboard. One reason is to prevent the thermostat setup from being changed by unauthorized people. The unlocking procedure is usually unknown to typical users. Another reason is to prevent the thermostat setup form being changed accidentally.
However, locking the keyboard may prevent other people to change the setup of the thermostat. Although this may be the intent of locking the keyboard, doing so may cause inconvenience to people who can properly use the thermostat. One example is the installation in a public area, e.g., an office. The thermostat is programmed to meet the office schedule. After the initial set up, the thermostat is often locked. However, in some scenarios people in the office may want to temporary adjust the room temperature. Consequently, in order to change the setting one may need to ask installation service to have it adjusted.
It is desirable to have a keyboard lock capability that restricts access in order to protect important setup settings but to allow limited adjustment of other settings.